package map;

import java.util.HashMap;
import java.util.Map;

public class MapDemo {
    public static void main(String[] args) {
        Map<String,Integer> map = new HashMap<>();
        Integer value = map.put("语文",98);
        System.out.println(value);
        map.put("数学",97);
        map.put("英语",96);
        map.put("物理",95);
        map.put("化学",98);
        System.out.println(map);
        value = map.put("语文",55);//替换value
        System.out.println(map);
        System.out.println(value);
        int size = map.size();
        System.out.println("size:"+size);
        value = map.get("英语");
        System.out.println("英语:"+value);
        value = map.get("体育");
        System.out.println("体育:"+value);
        value = map.remove("语文");
        System.out.println(map);
        System.out.println(value);
        boolean ck = map.containsKey("体育");
        boolean cv = map.containsValue(97);
        System.out.println("包含key:"+ck);
        System.out.println("包含value:"+cv);

        map.clear();
        System.out.println(map);
    }
}




